MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, China.
School of Computer Science and Technology, Dalian University of Technology, Dalian 116024, China.
Int J Biol Macromol. 2024 Nov;279(Pt 2):135219. doi: 10.1016/j.ijbiomac.2024.135219. Epub 2024 Aug 30.
Late blight, caused by Phytophthora infestans (P. infestans), is among the most devastating diseases affecting tomato and other Solanaceae species. Lipid transfer proteins (LTPs) represent a class of small, basic proteins that play a crucial role in combating biotic stresses. Previous studies have shown that SlLTPg1 most strongly responds after P. infestans infestation among the LTPs family in tomato. However, the function of SlLTPg1 in disease resistance remains unclear. Here, we constructed transient overexpression and VIGS-silenced plants of SlLTPg1. Our results revealed that SlLTPg1 plays a regulatory role in enhancing tomato resistance against P. infestans. This enhancement was attributed to the upregulation of defense-related genes and reactive oxygen species (ROS) scavenging genes, as well as increased enzymatic antioxidant activities. Importantly, we found that the SlLTPg1 protein significantly inhibited the growth of Fusarium oxysporum (F. oxysporum) by observing the zone of inhibition. Interestingly, we found smaller lesion diameters and upregulated expression levels of PR genes in transient overexpression SlLTPg1 of tobacco. Therefore, we further constructed transgenic tobacco lines of SlLTPg1, presenting evidence that overexpression of SlLTPg1 could positively regulate the resistance of tobacco to F. oxysporum. These findings revealed the role of SlLTPg1 in tomato resistance to P. infestans and tobacco resistance to F. oxysporum. Moreover, we propose SlLTPg1 as a potential candidate gene for augmenting broad-spectrum plant resistance against pathogens.
晚疫病由致病疫霉（Phytophthora infestans，P. infestans）引起，是危害番茄和其他茄科植物的最严重病害之一。脂质转移蛋白（LTPs）是一类小而碱性的蛋白质，在应对生物胁迫方面起着至关重要的作用。先前的研究表明，在番茄的 LTP 家族中，SlLTPg1 在受到致病疫霉侵袭后反应最为强烈。然而，SlLTPg1 在抗病性中的功能仍不清楚。在这里，我们构建了 SlLTPg1 的瞬时过表达和 VIGS 沉默植物。我们的结果表明，SlLTPg1 在增强番茄对致病疫霉的抗性方面发挥了调节作用。这种增强归因于防御相关基因和活性氧（ROS）清除基因的上调，以及酶抗氧化活性的增加。重要的是，我们发现 SlLTPg1 蛋白通过观察抑菌圈显著抑制了尖孢镰刀菌（Fusarium oxysporum，F. oxysporum）的生长。有趣的是，我们发现瞬时过表达烟草 SlLTPg1 的病变直径较小，PR 基因的表达水平上调。因此，我们进一步构建了 SlLTPg1 的转基因烟草株系，证明了 SlLTPg1 的过表达可以正向调节烟草对 F. oxysporum 的抗性。这些发现揭示了 SlLTPg1 在番茄抗致病疫霉和烟草抗尖孢镰刀菌中的作用。此外，我们提出 SlLTPg1 作为增强植物广谱抗病性的潜在候选基因。
